Investments (Components of Net Investment Gains Losses - Transaction Type) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Gain (Loss) on Securities [Line Items]
Realized gains (losses) on investments sold or disposed	$ (20)	$ (445)	$ (566)	$ (656)
Impairment (losses)	(898)	5	(905)	(35)
Change in allowance for credit loss recognized in earnings	(42)	84	(224)	(159)
Unrealized net gains (losses) recognized in earnings	16	(43)	54	(58)
Total recognized gains (losses)	(26)	41	(170)	(217)
Non-investment portfolio gains (losses)	(95)	(283)	(82)	(291)
Net investment gains (losses)	(1,039)	(682)	(1,723)	(1,199)
Impairment (losses)	(849)	$ 5	(856)	$ (35)
Reinsurance Risk Transfer Transaction
Gain (Loss) on Securities [Line Items]
Impairment (losses)	$ (841)
Commercial Mortgage Loans \| Reinsurance Risk Transfer Transaction
Gain (Loss) on Securities [Line Items]
Other Asset Impairment Charges			$ 44

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Amount of realized and unrealized gain (loss) on investment.

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Amount of gain (loss) on sale or disposal of other assets.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrealized gain (loss) on investment.

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